Vacuum release valve and method

ABSTRACT

A vacuum release valve and method are defined. The valve  10, 100, 200  is positioned on a line L between a pool suction inlet I and a pump PU for pumping pool liquid from the inlet and along the line L. The valve  10, 100, 200  includes a valve member  24, 108, 214  that is urged by the pump into a sealing position during normal pumping of pool liquid from the inlet to the pump, so that pool liquid does not flow across the valve. When a predetermined level of vacuum is induced in the line, the valve member is moved out of the sealing position by the vacuum so that a fluid is allowed to flow through the valve to release the vacuum.

FIELD OF THE INVENTION

The present invention relates to a vacuum release valve for positioningon a line between a pool suction inlet and a pump for pumping poolliquid from the inlet and along the line, and also relates to a vacuumrelease method. When the terminology “pool” is used in the presentspecification it includes swimming pools, spas, ponds, lakes etc.,especially when the aforementioned have recreational applications. Whenthe terminology “inlet” is used throughout the specification it caninclude one or more inlets of various types.

BACKGROUND OF THE INVENTION

Pools of various types are known to have one or more suction inletswhere pool water is sucked along a line via a pump to filtration,aeration, chemical treatment and other type of equipment, prior to beingreturned to the pool via one or more return outlets.

In more recent pool designs, some of the suction inlets are positionedat a bottom or lower region of the pool. Very recently developed poolcleaning systems, known as in-floor cleaning systems, have one or moresuction inlets which suck pool water therethrough and any debris andpollutants entrained therein are cleaned from the water by being pumpedto a filtration and/or treatment station.

Some of these inlets have relatively small opening areas and, when largevolumes of water are being pumped therethrough, very high suction forcesat the inlet can be induced. These forces can be so extreme that if apool user contacts the inlet by any part of their body, they can be heldthereagainst, unable to be dislodged even by excessive force. Where thesuction inlet is located at or adjacent to a bottom of the pool, theuser can thus be submerged with the risk of drowning, grievous bodilyharm etc.

U.S. Pat. No. 5,991,939 discloses a pool safety valve which is designedto bleed air into the suction line of a pool when the suction pressureexceeds a predetermined value. The arrangement disclosed is, however,somewhat complex in that a pair of opposing valve slide plates, whichare normally biased apart by a spring arrangement, must be urged awayfrom opposing sealing end plates by the suction force in the poolsuction line. The valve of U.S. Pat. No. 5,991,939, because of itsrelative complexity, is somewhat complex to manufacture and operate andwould therefore be relatively expensive.

U.S. Pat. No. 6,098,654 also discloses a flow blockage suction interruptvalve to instantaneously introduce atmosphere into a suction pipingsystem of a pool when a dangerous vacuum condition is detected. Thevalve of this patent is even more complex in construction and operationthan that of U.S. Pat. No. 5,991,939. In the valve of U.S. Pat. No.6,098,654, vacuum is applied to a spring loaded trigger pin, which drawsthat trigger pin down in the valve, and this in turn releases a lockingmechanism between a main valve piston and the remainder of the valve.Once this locking mechanism is released, a spring forces the main valvepiston downwardly, and this allows ambient air to flow through thevalve, past the piston and into the swimming pool circulation system.Because of its complexity and the close tolerances required, this valvewould be quite costly to manufacture and is complex in operation.

Increased complexity often means that a valve is more likely to seize orfail in use.

SUMMARY OF THE INVENTION

In a first aspect the present invention provides a vacuum release valvefor positioning on a line between a pool suction inlet and a pump forpumping pool liquid from the inlet and along the line, the valveincluding a valve member that is urged by the pump into a sealingposition during normal pumping of pool liquid from the inlet to the pumpand such that the pool liquid does not flow across the valve;

wherein, when a predetermined level of vacuum is induced in the line,the valve member is moved out of the sealing position by the vacuum sothat a fluid is allowed to flow through the valve to release the vacuum.

In the valve of the present invention, the valve member is urged by thepump into a sealing position during normal pumping of pool liquid fromthe inlet to the pump. This means that a very simple valve and valvemember configuration can be adopted and the complexities of prior artconfigurations avoided. For example, a simple valve ball and valve seatarrangement can be employed (as described below).

In one preferred application of the invention in a swimming pool, whenor if a user blocks the suction inlet by a part of their body (or ifother debris blocks the inlet) whilst the pump is operating, the pumpcontinues to pump the liquid in the line thus inducing a vacuum(typically a partial vacuum) in the line. The level of vacuum inducedthen typically rapidly reaches the predetermined level. The valve of thepresent invention can release that vacuum by allowing a fluid (eg. agas) to flow back into the line, thereby breaking the vacuum andreleasing the user (or debris). In effect, the flow of fluid can eithercause the pump to lose prime and hence suction force (eg. when the fluidis a gas) or can reduce the pressure in the line to a level where theuser (or debris) can be freed from the inlet (eg. when the fluid is aliquid).

The terminology “predetermined level” does not equate as such with anyspecific relative or even an absolute level of vacuum, but is typicallya level of vacuum reached when there is a blockage at the inlet.However, in other applications partial blockage may cause thepredetermined level of vacuum to be reached. Thus the terminology shouldbe interpreted broadly.

It should be appreciated that the invention has application with suctionlines in a wide variety of pools including natural and artificial ponds(eg. to prevent fish and other marine life from being harmed), in spas,and even in commercial applications. Thus, when “pool liquid” isreferred to, it is not necessarily limited to water, and could be bodiesof organic fluids etc.

Typically the valve allows a flow of fluid in the form of air or otherambient gas thereacross to release the vacuum, although in someembodiments the flow of fluid may also be a flow of liquid (eg arestorative side water flow from a separate source). However, for easeand cost of operation it is most preferred that the flow of fluid is aflow of air (typically atmospheric, ambient air, being readilyavailable).

Preferably the valve is a one way valve, more typically a one way ballvalve, with the valve member being a ball. Thus, in a normal pool liquidpumping operation, the ball seals fluid flow thereacross by sittingagainst a valve seat, and is only moved away from the seat when thepredetermined level of vacuum is induced in the line, thereby enablingthe fluid flow.

In one preferred variation the valve houses a plurality of valvemembers, typically a plurality of ball valve members. This enables thevalve to provide for multiple re-uses, prior to the valve having to bedismantled for servicing. In this regard, each ball valve member can beseparated from an adjacent ball valve member by a separator pin.

Typically the plurality of ball valve members are aligned one above theother, linearly above the valve seat. Preferably, when the predeterminedlevel of vacuum is reached, the ball sitting at the valve seat is drawnpast the seat and preferably into a ball capturing chamber. Inaccordance with the present invention, rather than having to discard thevalve or dismantle the valve to reset the ball at the seat, a user canremove the lowermost separator pin, the next uppermost ball can thendrop into place at the seat (eg. under the influence of gravity) and thevalve is therefore ready for use again.

Preferably, when the predetermined level of vacuum is reached, the ballsitting at the valve seat is drawn past the seat and into a ballcapturing chamber, and wherein an upper part of the valve can be rotatedrelative to a lower fixed part of the valve and, at a given rotationalposition, the upper part can then be moved downwardly relative to thelower part such that the valve seat passes over the ball in the ballcapturing chamber to once again position the ball at the seat, and theupper part can then be moved upwardly relative to the lower part so thatthe valve is again ready for use.

Preferably the upper part is urged downwardly against a springpositioned between the upper and lower parts, which spring tends to urgethe upper part away from the lower part and move it up once the ball hasagain been positioned at the seat.

Preferably the valve is located in an auxiliary line located laterallyto the line extending between the inlet and pump. As such, when poolliquid is pumped past the auxiliary line a partial vacuum is alsoinduced in the auxiliary line. Typically the valve seat is positionedsuch that this partial vacuum has the effect of drawing the ball againstthe seat, enhancing sealing thereat.

Preferably the valve is also oriented such that when the fluid is causedby the vacuum to flow across the valve the ball is forced past the seat.In this regard, the ball is, in effect, sucked out of its sealingposition at the seat by the suction force induced in the line, and ismoved to a position which then enables fluid to be drawn across thevalve to the pump, thus releasing the vacuum.

Preferably the seat is adapted to only allow the ball to move therepastonce the predetermined level of vacuum has been induced in the line.Preferably the seat is formed from a resilient but deformable material,which deforms as the ball passes and restores to its former shape oncethe ball has passed.

Preferably the seat is in the form of an annular inwardly protrudingshoulder or sealing ring in the valve, which preferably engages anunderside of the ball such that the ball can only move therepast whenthe predetermined level of vacuum is reached. Thus, preferably theretention shoulder is oriented such that, for normal pump operation, theball is not moved out of sealing engagement with the seat.

As an alternative to the retention shoulder arrangement, the ball can bespring loaded, or another retention system such as plurality of leafsprings etc. can be employed, but in any case a sealing arrangement isstill employed.

In a second aspect the present invention provides a method of using avalve to release a vacuum induced in a line between a pool suction inletand a pump for pumping pool liquid from the inlet and along the line,the valve having a valve member that is held in a valve closed positionby the pumping of pool liquid in the line, the member being movable fromthe closed position to an open position, the method including the stepof facilitating valve member movement to the open position, to therebyallow a flow of fluid into the line, when a predetermined level ofvacuum is induced in the line, to in turn release the vacuum.

Preferably the flow of fluid is a flow of air or other gas, andpreferably the method is facilitated by a vacuum release valve accordingto the first aspect of the invention (and its various preferred forms).

BRIEF DESCRIPTION OF THE DRAWINGS

Notwithstanding any other forms which may fall within the scope of thepresent invention, preferred forms of the invention will now bedescribed, by way of example only, with reference to the accompanyingdrawings in which:

FIG. 1 shows a schematic flow diagram illustrating the flow of poolliquid in a closed return circuit and including a vacuum release valvein accordance with the present invention;

FIG. 2 shows a side schematic sectional elevation of a first valvehousing for use in the flow circuit of FIG. 1, and schematicallyillustrating fluid flow pathways therethrough;

FIG. 3 is a partially exploded, partially sectioned side sectionalelevation of a first vacuum release valve in accordance with the presentinvention, also illustrating the valve housing of FIG. 2;

FIG. 4 is a side view in partially sectioned detail of the valve ballretention mechanism of FIG. 3;

FIG. 5 is an exploded sectional side elevation of a first valve ballhousing, being part of the valve of FIG. 3;

FIGS. 6A to 12A show side (typically sectioned) elevations of variouscomponents of a second vacuum release valve in accordance with thepresent invention, with FIGS. 6B to 12B showing either plan or undersideplan views respectively of those components, and with FIGS. 11C and 12Cshowing details of the respective components in FIGS. 11A and 12Arespectively;

FIG. 13 shows an assembled cross-sectional elevation of the secondvacuum release valve in accordance with the present invention;

FIGS. 14, 16, 19, 21 and 23 show side sectional elevations of variouscomponents of a third vacuum release valve in accordance with thepresent invention, with FIGS. 15 and 17 showing underside plan viewsrespectively of FIGS. 14 and 16, and with FIGS. 20, 22 and 24 showingplan views respectively of FIGS. 19, 21 and 23, and with FIG. 18 showinga partial side elevation of the component of FIGS. 16 and 17; and

FIG. 25 shows an assembled cross-sectional elevation of the third vacuumrelease valve in accordance with the present invention.

MODES FOR CARRYING OUT THE INVENTION

Referring firstly to FIG. 1, a vacuum release valve 10 is positionedin/on a flow line L for a pool P. As stated above the pool P can be anypool or pond type including spas, ponds, natural and artificial bodiesof water etc. However, the apparatus described hereinafter is mostsuitable for use in swimming pool applications.

Pool liquid (typically water) is pumped through the flow circuit viapump PU, with water being drawn into the line L at suction inlet I, thenpassing via a skimmer box SB and the valve 10, and then via a non-returnvalve NR to the pump. From the pump, the water is passed via afiltration and/or treatment unit F & T, and is then returned to the poolby one or more outlets O.

The valve 10 in accordance with the present invention enables a vacuumrelease or vacuum break function, should the inlet be fouled or blockedin any way. Most importantly the vacuum release function operates shoulda human user or other sizeable living organism block or have part oftheir body sucked against the inlet in potentially perilouscircumstances whilst the pump is operating.

In this regard, should the inlet become blocked for any of these variousreasons, whilst the pump is continuing to operate, then water in line Lcontinues to be drawn by the pump, but because of the blockage at inletI, the advancing head of water creates a vacuum (typically a partialvacuum) therebehind, thus increasing the suction force at inlet I, andmaking it more difficult for the blocking member to be released. Valve10 in accordance with the present invention is so designed andconfigured that once that vacuum reaches a predetermined level (inpractice this occurs rapidly after blockage) the valve opens to enablefluid to be discharged into line L to release or break the vacuum.

The fluid is typically an ambient gas such as air that flows across thevalve and breaks the prime in the pump. However, if the fluid is aliquid (such as water) it can flow into the pump and, in effect, nullifythe suction force in line L to a level sufficient to release theblockage at the inlet, thus breaking the vacuum.

FIG. 2 illustrates a valve housing 12 for valve 10 and illustratesliquid and fluid flows through the housing, with arrows F indicating thenormal flow of pool liquid through the housing from the inlet I via lineL to the pump PU. The arrow R indicates the flow of a fluid through thevalve housing into the line L to release any vacuum induced in the lineL.

Referring now to FIGS. 3 and 4, the valve 10 is shown in greater detailand its operation will now be described. The valve 10 includes a valvebody 14 having a plurality of (for example 3) equidistantly spacedpassages 16 defined therethrough, each for allowing a flow of fluid(typically air) into the valve. Referring also to FIG. 5, a supportingbase plate 18 is mounted in the valve body 14 and a holder 20 is screwfitted into this plate. A sealing member 22 is then positioned in holder20, the member having an inwardly projecting annular shoulder 23 definedat its lower opening for retaining (seating) a valve ball 24thereagainst in a sealing arrangement. The valve ball is also housed inmember 22 as shown. The shoulder can include radial cuts or separationstherein to define a plurality of tabs or fingers engaging against thelower side of ball 24 (as shown in FIG. 4) providing that a seal isstill defined. The shoulder is designed to prevent the valve ball frombeing sucked therepast by normal pump operative suction force. However,as described below, when the suction force at the ball exceeds thenormal pump suction force by a predetermined amount, then the shoulderdeforms to allow the ball to move therepast.

A restraining cap 26 is located on top of member 22 to cover the ball 24and hold it in place as shown. The member 22 and cap 26 are then heldwithin holder 20 by a retaining nut 28 which is screwed down into holder20 until it clamps against the cap and sealing member combination. Theassembled valve arrangement is held within the body 14 via a hollowretaining cylinder 30 which has holes formed therethrough that alignwith passages 16 as shown. The resulting assembled arrangement has acentral fluid flow passage 32 defined therethrough which is closed asappropriate by valve ball 24 (described hereafter).

The upper end of the valve body is closed by a weather cap 34 which fitsover the exposed end of cylinder 30. A union nut 36 is fitted around theoutside of the valve body and is slid down over the body until it sitsagainst annular projecting shoulder 38.

A lower skirt 40 of the valve body is sized to fit snugly within recess42 of an auxiliary line in the form of valve housing stem 44, until theunderside of shoulder 38 abuts the stem upper end 46. When the valvebody has been located in stem 44, the union nut is screwed onto externalthreading 47 on the stem end to lock the valve body to the valvehousing. In this regard, to facilitate a fluid tight seal, an O-ring 48can be located at the underside of shoulder 38 to be compressed betweenthe shoulder underside and the stem upper end.

The skirt 40 also has an end cap 50 fitted therein to define a chamber51 in the end of the valve body 14. The cap 50 has a plurality of fluidoutlet passages 52 defined therein from which a fluid stream A(typically air) passing through the valve can be discharged into theinterior of stem 44.

The valve housing 12 further includes a main pipe section 54, and boththe right hand end 56 and left hand end 58 of the main pipe section(only the right hand end is shown in detail in FIG. 3) are adapted forhaving the line L coupled thereto (eg by a union nut 60 that is screwedonto an external thread of the line L (not shown)).

When assembled, pool liquid typically flows through the main pipesection 54 as a stream F (ie as drawn by the pump PU). This flowingliquid also induces a partial vacuum in stem 44, which, in addition togravity, helps to draw the ball 24 against the shoulder 23, thusenhancing the seal. Pool liquid is prevented from flowing through thevalve 10 because the central passage 32 is closed by the valve ball 24(ie the valve ball is held against the sealing member shoulder 23 bynormal operating suction resulting from stream F and is also maintainedin place by the restraining cap 26).

Should the inlet I become blocked during pump operation for whateverreason, then the continued action of the pump continues to extractliquid from the line L and through the valve housing 12. As no furtherliquid can flow in via the inlet (ie because of the blockage) then avacuum (typically a partial vacuum) is induced in the line L. Thecontinued operation of the pump then makes removal of the blockingobject, (eg. a user, debris etc.) extremely difficult, because of theadditional suction force created by the vacuum.

This suction force is transmitted via the line L to the valve. Theadditional suction typically rapidly reaches a predetermined level overand above the normal pump suction and hence causes ball 24 to be suckeddownwardly, moving past the inwardly projecting shoulder 23 (which isdeflected/deformed downwardly but which typically returns to itsoriginal position once the ball has moved therepast). Ultimately, theball drops into the chamber 51, thereby opening passage 32 to fluidflow. In this regard, a stream, usually an air stream A, can then passthrough the valve from the valve surroundings and via the passages 16.The stream A then passes through central passage 32, and ultimatelyexits the valve by outlet passages 52. This stream of fluid (depicted byarrow R in FIG. 2) restores the normal pressure in line L, breaking orreleasing the vacuum induced in the line and enabling the body or debrisattached at inlet I to be readily released therefrom.

The use of sealing member 22 is preferred because of its durability.Also it can be easily formed from a non corrodible material (eg aninjection mouldable plastic). This optionally enables the shoulders 23to be defined as a series of discrete inwardly projecting tabs orfingers to further facilitate deformation/deflection and thenrestoration as the ball 24 moves therepast. However, the sealing member22 can also be replaced by an appropriately formed sealing spring, forexample, that extends upwardly from cap 50 and sealingly engages againstthe underside the valve ball 24. A helical spring can be employed thatis formed from a non corrodible material (eg stainless steel), or one ormore leaf springs or other types of biasing member can be used inconjunction with a sealing arrangement.

Another advantage that follows from employing the sealing member 22 isthat the valve ball, once released from the sealing member, stayspermanently released and is not urged back up into a sealingarrangement. This, on the other hand, might occur with a malfunctioningspring, or where the suction pressure is only partially overcome. Inother words, use of the sealing member as described provides an in-builtfailsafe feature.

In a typical operation of the first valve embodiment, once the ball hasbeen urged out of its original position, the user must either replacethe valve entirely or disassemble the valve and replace variouscomponents thereof (eg. member 22). However, referring now to the valveof FIGS. 6 to 13, a second valve embodiment will be described where,once a first ball has moved past the sealing member, further valve ballswithin the valve can successively be moved to replace that valve ball,without the user having to replace or disassemble and service the valve,until all supply of valve balls within the valve have been used up.

The components of the second valve embodiment will firstly be describedand then reference will be made to the assembled valve embodiment. Thesecond valve 100 (FIG. 13) includes a cylindrical cap extension piece102 (FIGS. 6A and 6B). The cap extension piece maintains a sealing ring104 (FIGS. 7A and 7B) in place within the valve. The sealing ring 104has a tubular body portion 106 into which ball valves 108 (FIG. 13) areloaded. A circumferential flange 110 projects outwardly from a lower endof the body portion 106, and an annular step 112 protrudes downwardlyfrom the periphery of flange 110. This step retains a ring-shaped valveseat 114 as described below with reference to FIG. 13.

The external diameter of the cap extension piece 102 and the sealingring circumferential flange 110 are set such that they fit snugly withinan upper part 116 of second valve body 118 (the valve body beingillustrated in FIGS. 9A and 9B). The valve body has a lower part 120,which is inset with reference to the upper part and is separatedtherefrom by an internal wall 122. The seat 114 is retained between theinternal wall and annular step 112 of sealing ring 104 (as shown in FIG.13).

A central opening 124 is defined in the internal wall 122, with acylindrical skirt 126 projecting downwardly from the internal wall andsurrounding the lower side of central opening 124. The opening 124 andskirt 126 provide a guide passage for a ball that is drawn past seat 114(i.e. when a suction force is applied to the valve).

Mounted to the lower part 120 of the valve body 118 is an internalbreather member 128. The bottom wall of the breather member is providedwith four equidistantly spaced holes 130 for allowing a flow of fluidthrough the valve. A central pinhole 132 is also provided in the bottomwall of the breather member 128 for receiving an internal breather pin134 therein (see FIGS. 10A and 10B, and FIG. 13). Protruding out fromthe internal breather member sidewall 136, intermediate the top andbottom of that wall, is a circumferential retaining flange 138, whichabuts the underside of valve body lower part 120 so that the breathermember 128 can be affixed thereto (e.g. by adhesive, by screw mounting,etc.)

As indicated above, FIGS. 10A and 10B depict the internal breather pin134. The breather pin has an enlarged head 135 and a short shank 137,the shank fitting into central pinhole 132. The function of the breatherpin is to locate an internal breather seal 139. The breather sealfunctions to prevent the ingress of pool suction water into the valvewhen backpressure is applied to the valve (eg. by the pump).

FIGS. 11A and 11B depict one of the retaining pins 140 used in thesecond valve in accordance with the present invention. The retaining pinhead 142 has a slot 144, typically for receiving a screwdrivertherewithin. Pin shank 146 comprises a long, round (in cross-section),and in-use rotatable section 148 connected, via a snap region 150, to ashort in-use fixed section 152. FIG. 11C shows the snap region 150 indetail. When each retaining pin 140 is mounted in the valve, the shortsection 152 is fixed against rotation, whereas the long section 148 isable to be rotated. Thus, when a user inserts a screwdriver into slot144 and rotates it, the pin snaps at region 150, enabling the bulk ofthe pin shank to be removed from the valve (thus freeing an adjacentvalve ball 108—described below).

Referring now to FIGS. 12A to 12C the second valve vent cap 154 has aplurality (typically six) equidistantly spaced air vent holes 156extending therearound, each hole communicating with an air vent channel158 extending up into the cap. The vent channels enable the air ventholes to communicate with the cap interior once the cap is fitted ontothe valve.

The cap sidewall 160 is provided with a plurality of elongate ribs 162,typically equidistantly spaced therearound. The ribs allow for a sealingtape to be wrapped around the cap, once fitted on the valve, and preventthe tape from blocking the air vent holes 156. The ribs also prevent theinadvertent sealing of the cap at the valve when material is wrappedaround it in an attempt to seal it. Two opposing pin slots 164 are alsodefined in the cap sidewall 160, with each slot having a lower squaresection 166 (see detail in FIG. 12C). The length of slots 164 is greaterthan the length of holes 156. These slots enable the upper retaining pin140 to be fitted to valve body 118 prior to the cap 154 being fitted tothe valve.

Typically the short section 152 of pin 140 is chemically welded to thecap 154 at slot 164, preventing its rotation within the slot. As analternative or in addition to chemical welding, the short section 152can be provided with a square cross section, such that it fits snuglywithin the square section 166 of slot 164, thereby preventing itsrotation therewithin. The rotatable section 148, is circular incross-section and rotates within its respective slot 164. Accordingly,rotation of the pin head 142 causes the pin to snap at 150, allowing thepin head and shank long section 148 to be removed from the valve. Inthis regard, the long section may also be threaded to facilitate theinitial fastening of the pin in the assembled valve.

FIG. 13 shows second valve 100 in an assembled configuration. As can beseen, three valve balls 108 are positioned within the assembled valve,separated by two retaining pins 140. The lowermost valve ball 108 sitsagainst seat 114 in a sealing arrangement (akin to the sealingarrangement described for the first valve 10) and is held thereat by apartial vacuum induced by the liquid passing stem 44. The lowermost pin140 typically does not function to retain the lowermost ball 108 againstseat 114. The valve functions as a one-way valve, but the ball 108 issealed at the seat 114 partly by gravity and partly by vacuum caused bypool suction water flowing in line L.

Typically the valve 100 is positioned in/on a flow line L for a pool Pin the same manner as valve 10. Thus, should the inlet become fouled orblocked in any way, the lowermost valve ball 108 is sucked past seat114, and passes through opening 124, skirt 126 and into the breathermember 128. However, rather than the user having to dismantle the valveto reset ball 108 into its original sealing position, the user simplyremoves the lowermost retaining pin 140 (i.e. by screwing head 142,detaching section 148 from fixed section 152 and removing the head andthe long section of the pin from the valve. This enables the nextuppermost ball valve to drop into position on the seat 114. The valve istherefore operable again for normal pumping. When, once the second ballvalve has been sucked past the seat 114 and into the internal breathermember, the uppermost retaining pin can be removed to release theuppermost valve ball to again drop down and sit against the seat 114.

This arrangement extends the useable life of the valve and means thatthe user does not have to replace the valve after each vacuum releaseoperation thereof.

It should be noted that, once the seated ball has been sucked intomember 128, air is able to flow into the valve via air vent holes 156,air vent channels 158, then into the underside of the cap 154, andthence past the two uppermost balls 108, flowing between those balls andthe tubular body portion 106. The air then flows through seat 114,through central opening 126, into the breather member 128, and then outinto line L via holes 130.

Usually the valves 10, 100 are located adjacent to the pump (eg in apump and filter housing) to be located out of the way of tampering orother interference.

Typically most of the components of the valve are formed from a plasticsmaterial (optionally an injection mouldable plastic). Typically thevalve ball(s) are formed from stainless steel or similar non-corrodiblematerial.

Referring now to FIGS. 14 to 25, where like reference numerals denotesimilar or like parts, a third valve embodiment will now be described.In this embodiment, the valve is reusable, in the sense that the valveball can be used a number of times. More particularly, an upper part ofthe valve is movable with respect to a lower part of the valve, thevalve ball initially being seated in the upper part of the valve, andbeing drawn by suction into the lower part of the valve. The upper partcan then be moved into the lower part to reseat the ball therein.

Some of the valve components are identical to the valve described inFIGS. 6 to 13. In particular, the components shown in FIGS. 6, 10 and12, namely, the cap extension piece 102, the breather pin 134 and thecap 154 are identical. However, the remaining components differ andvalve 200 will therefore now be described.

Referring firstly to FIG. 25, the valve generally comprises an upperpart 202 which is movable with respect to a lower part 204. In thisregard, in a normal mode of operation of the valve, the upper part hasthe orientation as depicted in FIG. 25, and in this orientation theupper part cannot be moved downwardly with respect to the lower part.However, the upper part can be rotated (typically anticlockwise) withrespect to the lower part and, as described below, the extent of thisrotation is delimited by appropriate stops to a predetermined maximum.When the upper part has been rotated to this predetermined position, itcan then be moved downwardly with respect to the lower part, telescopingthereinto. This telescoping movement is also delimited, and thelowermost position of the upper part corresponds with a ball retrieval(or recapture) position, so that when the upper part is returned to itsoriginal (start) position, it has recaptured the ball. This procedurewill be described in detail below, after first describing the componentsof valve 200.

The upper part 202 includes cap 154 which is attached to cap extensionpiece 102. The cap extension piece is in-turn affixed at its lower endto the circumferential flange 206 of sealing ring 208 (FIGS. 19 and 20).The sealing ring 208 is similar to the sealing ring 104 of FIG. 7, butin this third valve embodiment it does not include an annular step 112for retaining the valve seat. Rather, it has a planar base whichfunctions as described below. The sealing ring has an upstanding bodyportion 210. As shown in FIG. 25, a retaining pin 212 is insertedthrough the body portion 210 to retain a ball valve 214 in the sealingring during transportation and installation of the valve.

The valve upper part 202 further includes a reset slide 216 (FIGS. 16 to18) which includes an upper cavity 218 into which a combination of thecap extension piece 102 and sealing ring 208 is received. Thecircumferential flange 206 of the sealing ring is affixed at itsunderside to the reset slide when mounted in the upper cavity 218. Acentral horizontal wall 220 of the reset slide has a stepped centralpassage 222 therethrough, the step defining an annular ledge 224 intowhich a valve seat 226 (FIG. 25) is received. As shown, the planarunderside of the sealing ring 208 retains the valve seat 226 within thestepped central passage and against the annular ledge 224. The valveseat 226 can either be fixed in position at the ledge or can be a freelymovable, self-centreing O-ring. Typically the valve seat is made of adeformable material, such that the ball valve 214 can be urged therepastwhen a predetermined level of vacuum is caused in the line L.

Protruding downwardly from wall 220 is an annular flange 228,surrounding the stepped central passage and defining, on an opposingside of the annular ledge 224, a second annular ledge 230. This secondannular ledge receives and supports the upper end of a helical spring232 (FIG. 25) the function of which is described below. As shown in FIG.17, the annular ledge also has a gap 234 defined therein into which ahooked end of the spring 232 can be received to fasten the spring to thereset slide 216 when it is rotated (as described below).

Projecting downwardly from the wall 220 are three evenly spaced resetplates 236 A, B and C. The reset plates are each inset from thecircumference of the reset slide. Each reset plate has a latching recess238 defined therein, the function of which is described below.

An upper circumferential side wall 240 of the reset slide includes acircumferential notch 242 defined therein, and into which a sealingO-ring 244 (FIG. 25) is fitted when the valve is assembled. This O-ringprovides a seal between the valve upper part 202 and lower part 204 whenthe valve is in operation, and facilitates a smooth movement of theupper part with respect to the lower part during valve reset (ie. duringrotation and sliding of the upper part with respect to the lower part).

Thus, the valve upper part 202 includes cap 154, cap extension piece102, sealing ring 208, retaining pin 212, reset slide 216, valve seat226 and O-ring 244. As described above, this valve upper part can berotated and slid telescopically as a unit with respect to the valvelower part 204.

The valve lower part 204 includes a slide housing 246. The slide housingis essentially a cylindrical piece (as shown in FIGS. 14 and 15) butincludes an inwardly projecting annular flange 248 at its upper end,which retains the upper side wall 240 of reset slide 216, and thusprevents the valve upper part 202 from being withdrawn out of the valvelower part 204.

As shown in FIG. 25, the slide housing 246 is mounted to a union bodymale half 250 (eg. affixed thereto). The union body male half 250 issimilar to the body 14 of FIG. 3, and is couplable to the stem upper end46 (FIG. 3) via a union nut 36. At its upper end, the union body malehalf has an external circumferential ledge 252 against which the lowerend of the slide housing abuts, so that the upper end of the union bodymale half is received within the slide housing 246.

The upper end of the union body male half 250, in combination with theslide housing 246, further defines an internal circumferential ledge 254at which a slide guide 256 (FIGS. 21 and 22) is supported. The slideguide includes a horizontal upper wall 258, with three cutaway recesses260 defined in that wall (FIG. 22). Projecting downwardly from that wallare three discrete wall sections 262, which sit adjacent to and locatethe slide guide in the upper end of the union body male half 250 (asshown in FIG. 25). In addition, a circular passage 264 is definedthrough this slide guide, and a downwardly projecting annular flange 266surrounds that passage. The annular flange 266 helps to support andguide the helical spring 232 (as shown in FIG. 25).

The cut-away recesses 260 are each spaced and sized such that acorresponding reset plate 236 can be received therethrough. This enablesthe valve upper part to be telescopically extended into the valve lowerpart, as described below.

The valve lower part also includes a reset breather rod 268 (FIGS. 23and 24). The reset breather rod includes a lower body portion 270 havinga laterally projecting circumferential flange 272 which abuts and issupported at an internal annular ledge 274 at a lower part of the unionbody male half 250 (FIG. 25). Extending up from the body portion 270 isa tubular portion 276 having a bore 278 therethrough such that the ballvalve 214 sits against the top end of portion 276 after it has beensucked passed the valve seat 226. As can be seen, the tubular portion276 extends centrally through and generally centres the helical spring232.

Located within an annular recess 280 in the body portion 270 are twoupstanding spigots 282. The spigots capture a lower end of the helicalspring between themselves, and between themselves and an external ledge284 at the base of tubular portion 276 (as best shown in FIG. 25). Thusthe spring 232 is attached at its upper end to the valve upper part andat its lower end to the valve lower part.

A central horizontal wall 286 of the body portion 270 has four evenlyspaced holes 288 therethrough for the release of fluid (typically air orother gas) from the valve and into the line L when a suction force isapplied to the valve.

In addition, a small bore 290 extends through the central wall 286 andopens onto bore 278. A breather seal retaining pin 134 (being the sameas the breather pin of FIGS. 10 and 13) has a central spigot 137 thatextends up and into the small bore 290 (typically in a push fit orinterference fit) to retain a breather sealing member 292 at the otherside of body 270, thus sealing the lower end of the valve. The breathersealing member 292 is formed of a flexible or deformable material (andis essentially the same as breather seal 139).

Reference will now be made to FIG. 25, which shows the assembled valve200 in cross-section, to describe the operation of the valve.

For normal pool pump suction, the ball valve 214 is located in the upperof the two positions shown in FIG. 25. In this position the ball sitswithin the sealing ring 208 and rests against the valve seat 226.Typically the ball valve sits against the seat under the influence ofgravity and/or suction generated in the valve by pool water flowing inline L. No ambient air passes through the valve in this orientation.

When there is a blockage in line L (eg. because of a body or debrisbecoming attached at inlet I) a vacuum is generated in line L, and thevalve 200 then comes into operation. The ball valve 214 is sucked passedthe valve seat 226 and drops into a lower ball capturing chamber 298.Once in this position a fluid, typically air, can flow into and throughthe valve via cap 154. The air flows through the air vent holes 156,through the sealing ring 208, around the ball valve 214 in chamber 298,then flowing between and around the coils of spring 232, around theoutside of the tubular portion 276, through the union body male half250, into the annular recess 280 of body portion 270, and thence throughthe holes 288. In so flowing, the air deflects the breather sealingmember 296 away from the body portion, and then flows into line L. Thiscauses the pump to lose prime, and this releases the vacuum in line L sothat the body or debris can be freed from the inlet I.

Advantageously, in accordance with this embodiment of the invention, thevalve has a reset mechanism, which enables the ball valve to be restoredto its original upper position so that the valve is ready for operationagain. In this regard, and as described above, the valve upper part isrotatable and telescopically extendable into the valve lower part torecapture the ball valve 214 above valve seat 226.

Specifically, a user typically grasps the cap 154 and rotates itanticlockwise. This anticlockwise movement is translated via the capextension piece 102 and the sealing ring 208 to the reset slide 216.

In one mode of operation, the valve upper part can be set in a “charged”orientation whereby the reset plates 236 A, B and C extend partly intorespective cut-away recesses 260, so that the plates abut a respectiveedge of each cut-away recess 260 at their latching recess 238. In thisorientation, the spring has been partly wound or twisted.

In another mode of operation, rotation of the reset slide is such as tocause the reset plates 236 A, B and C to move across the upper wall 258of the slide guide, until the plates completely align above theirrespective cut-away recesses 260. However, during this rotation, a usercan simultaneously push down on the cap 154, and will then detect thatthe plates are moving into alignment with their respective cut-awayrecesses, when the plates drop down partially into those recesses as theslide guide upper wall 258 abuts with the plates at the latchingrecesses 238 In either mode, the rotation of cap 154 twists spring 232.

In any case, continued rotation of the cap eventually allows for eachreset plate 236 to be urged downwardly into its respective cut-awayrecess 260, thus enabling the valve upper part to be telescopicallyextended into the valve lower part.

When the valve upper part is telescopically extended in this manner, thehelical spring is compressed whilst the ball valve 214 is maintained inthe ball capturing chamber 298. Eventually the valve seat 226 engagesand is then forced over and around the ball valve 214. The usercontinues to push down on the valve upper part, until the annular flange228 abuts the upper wall 258 of slide guide 256. This abutment indicatesto the user that the ball valve 214 is now sitting above the valve seat226, and that the user may now release the cap, so that the cap is urgedback and upwardly by the compressed helical spring 232.

Eventually the reset plates 226 pass out of their respective cutawayrecesses 260 and are located above the slide guide 256 so that the capcan be rotated back to its original (start) position. In this regard,the twist in the helical spring 232 re-rotates the valve upper part 202back to its original position.

In this manner, a user does not need to discard or dismantle the valveafter it has been “tripped”. However, typically after many such resetoperations, the valve seat loses its shape memory and is permanentlydeformed, so as that it can no longer provide an effective seal at thevalve seat. At this time, the valve is either discarded, or can bedeconstructed or dismantled and the valve seat 226 replaced.

Whilst the invention has been described with reference to a number ofpreferred embodiments, it should be appreciated that the invention canbe embodied in many other forms.

What is claimed is:
 1. A vacuum release valve for positioning on a linebetween a pool suction inlet and a pump for pumping pool liquid from theinlet and along the line, the vacuum release valve including a valvemember that is urged by the pump into a sealing position during normalpumping of pool liquid from the inlet to the pump and such that poolliquid does not flow through the vacuum release valve; wherein thevacuum release valve is adapted for location in an auxiliary linelocated laterally to the line extending between the inlet and pump suchthat, when pool liquid is drawn past the auxiliary line, the suctioninduced in the auxiliary line has the effect of drawing the valve memberagainst the seat; wherein, when a predetermined level of vacuum isinduced in the line, the valve member is moved out of the sealingposition by the vacuum so that a fluid is allowed to flow through thevacuum release valve to release the vacuum; and wherein the seat isadapted to only allow the valve member to move therepast once thepredetermined level of vacuum has been induced in the line, the seatbeing formed from a resilient but deformable material, which deforms asthe member passes but restores to its former shape once the member haspassed.
 2. A valve as claimed in claim 1 wherein the valve member is aball and the seat is in the form of an annular inwardly protrudingshoulder or sealing ring in the valve, which engages an underside of theball but such that the ball can move therepast only when thepredetermined level of vacuum is reached.
 3. A valve as claimed in claim1 wherein the fluid is ambient air.
 4. A valve as claimed in claim 1wherein the valve is a one way valve.
 5. A vacuum release valve forpositioning on a line between a pool suction inlet and a pump forpumping liquid from the inlet and along the line, the vacuum releasevalve including a valve member that is urged by the pump into a sealingposition during normal pumping of pool liquid from the inlet to the pumpand such that pool liquid does not flow through the vacuum releasevalve; wherein the vacuum release valve is adapted for location in anauxiliary line located laterally to the line extending between the inletand pump such that, when pool liquid is pumped past the auxiliary line,a partial vacuum is induced in the auxiliary line, having the effect ofdrawing the valve member against the seat; wherein the seat is adaptedto only allow the valve member to move therepast once the predeterminedlevel of vacuum has been induced in the line, the seat being formed froma resilient but deformable material, which deforms as the member passesbut restores to its former shape once the member has passed, wherein,when the valve member is a ball, the seat is in the form of an annularinwardly protruding shoulder or sealing ring in the valve, which engagesan underside of the ball but such that the ball can move therepast onlywhen the predetermined level of vacuum is reached; wherein, when apredetermined level of vacuum is induced in the line, the valve memberis moved out of the sealing position by the vacuum so that a fluid isallowed to flow through the vacuum release valve to release the vacuum.6. A vacuum release valve for positioning on a line between a poolsuction inlet and a pump for pumping pool liquid from the inlet andalong the line, the vacuum release valve including a valve member thatis urged by the pump into a sealing position during normal pumping ofpool liquid from the inlet to the pump and such that pool liquid doesnot flow through the vacuum release valve; wherein the vacuum releasevalve is a one way ball valve, with the valve member being a ball, suchthat during normal pumping of pool liquid the ball seals fluid flowacross the valve by sitting against a valve seat, and is only moved awayfrom the seat by the fluid when the predetermined level of vacuum isinduced in the line; wherein, when a predetermined level of vacuum isinduced in the line, the ball is moved out of the sealing position bythe vacuum so that a fluid is allowed to flow through the vacuum releasevalve to release the vacuum, and the ball is drawn past the seat andinto a ball capturing chamber, and wherein an upper part of the valvecan be rotated relative to a lower fixed part of the valve and, at agiven rotational position, the upper part can then be moved downwardlyrelative to the lower part such that the valve seat passes over the ballin the ball capturing chamber to once again position the ball at theseat, and the upper part can then be moved upwardly relative to thelower part so that the valve is again ready for use.
 7. A valve asclaimed in claim 6 wherein the upper part is urged downwardly against aspring positioned between the upper and lower parts, which the springtends to urge the upper part away from the lower part and move it uponce the ball has again been positioned at the seat.
 8. A valve asclaimed in claim 6 wherein the fluid is ambient air.
 9. A valve asclaimed in claim 6 wherein the valve seat is adapted to only allow thevalve member to move therepast once the predetermined level of vacuumhas been induced in the line, the seat being fanned from a resilient butdeformable material, which deform as the member passes but restores toits former shape once the member has passed.
 10. A valve as claimed inclaim 6, wherein the seat is in the form of an annular inwardlyprotruding shoulder or sealing ring in the valve, which engages anunderside of the ball but such that the ball can move therepast onlywhen the predetermined level of vacuum is reached.
 11. A valve asclaimed in claim 6 that is adapted for location in an auxiliary linelocated laterally to the line extending between the inlet and pump suchthat, when pool liquid is pumped past the auxiliary line, a partialvacuum is induced in the auxiliary line, having the effect of drawingthe valve member against the seat.
 12. A vacuum release valve forpositioning on a line between a pool suction inlet and a pump forpumping pool liquid from the inlet and along the line, the vacuumrelease valve including a valve member that is urged by the pump into asealing position during normal pumping of pool liquid from the inlet tothe pump and such that pool liquid does not flow through the vacuumrelease valve; wherein the vacuum release valve is a one way ball valve,with the valve member being a ball, such that during normal pumping ofpool liquid the ball seals fluid flow across the valve by sittingagainst a valve seat, and is only moved away from a seat by the fluidwhen the predetermined level of vacuum is induced in the line; wherein,when a predetermined level of vacuum is induced in the line, the valvemember is moved out of the sealing position by the vacuum so that afluid is allowed to flow through the vacuum release valve to release thevacuum; wherein, when the predetermined level of vacuum is reached, theball sitting at the valve seat is drawn past the seat and into a ballcapturing chamber, and wherein an upper part of the valve can be rottedrelative to a lower fixed part of the valve and, at a given rotationalposition the upper part can then be moved downwardly relative to thelower part such that the valve seat passes over the ball in the ballcapturing chamber to once again position the ball at the seat, and theupper part can then be moved upwardly relative to the lower part so thatthe valve is again ready for use, wherein the upper part is urgeddownwardly against a spring positioned between the upper and lowerparts, which spring tends to urge the upper part away from the lowerpart and move it up once the ball has again been positioned at the seat.